function LDA_A( class_cell )
% number of class
    class_number = size(class_cell);

    %number of observations of each class
    data_size = [];
    for i = 1:1:class_number
        single_class_number = size(class_cell{i}, 1);
        data_size = [data_size single_class_number];
    end

    %mean of each class
    data_mean = [];
    for i = 1:1:class_number
        single_class_mean = mean(class_cell{i});
        data_mean = [data_mean ; single_class_mean];
    end 

    total_mean = mean(data_mean);

    % Center the data
    for i = 1:1:class_number
        center_data{i} = class_cell{i} - repmat(data_mean(1,:), data_size(i), 1);
    end 

    %Calculate the within class variance (SW)
    SW = 0;
    for i = 1:1:class_number
        SW = SW + center_data{i}' * center_data{i}
    end
    invsw = inv(sw)

    %SB 
    SB = 0;
    for i = 1:1:class_number
            SB = SB + data_size(i) * ((data_mean(i,:) - total_mean) * (data_mean(i,:) - total_mean)'
    end

    v=invsw*SB
    % find eigne values and eigen vectors of the (v)
    [evec,eval]=eig(v)
    

end

